I'm super stoked to be able to do the jam this year, but I have a confession to make. I am going to cheat. I mean, technically, according to the FAQ, cheating is allowed. So it's not really cheating. But I'll still feel bad.
I'm planning to work on a pretty ambitious project. Basically, the game is going to be a template for users of the Torque 3D engine who want to make an FPS. The engine already has an FPS template, but it's kind of difficult to work with, and doesn't actually have many good FPS features. There are more details here, including a link to the blog post where I announce the thing and people discuss it.
So, despite 7DFPS's motto of 'keeping shooters interesting', I will be striving to make a fairly run-of-the-mill example shooter, so that other people can make interesting shooters. Hurrah. Features I want include:

Co-op multiplayer

Vehicles

Enemy AI

Clean code... which will probably be the most challenging part!

So how is this cheating? Well, I've already started working on it. "You dastardly villain!" you may exclaim, but wait, attend my tale before leaping to a conclusion! Because of the ambition of this project, and because I have an important exam at the end of the jam week, I have decided to split the task.
This week, I will be creating the game's infrastructure: menus, options, the client/server architecture (including, hopefully, a master server), etcetera. I'll also be drawing up level design, and implementing similar gameplay systems for practise. Next week, during the jam itself, myself and hopefully a small cadre of elite superheroes will be creating the game's actual content - meshes, environments, level scripts and so on.
Here's the main menu so far:
Not too exciting, but I like it. The most impressive part is not its appearance, but the fact that it works with mouse, keyboard, and gamepad. This is not something Torque templates have done before. Seems basic, right? Well I think it should be.
Please forgive me.

Cool to see Torque make an appearance, and nice template.
Using an engine/template etc is not cheating btw - the jam is about reviving the fps genre and how you do that wont matter. It's not a software engineering challenge - as some might think!

Y Arriba el Torque!!!
Best Luck senor Buckmaster - I'm doing a similar thing with my Torque submission, essentially building my code/script template now and starting the actual game on the 8th - can't wait to see what you come up with!

Whoah, great to see you Gibby! Likewise, can't wait to see what you get up to :).
I'm always surprised to not see much (read: any_ Torque representation here given how geared it is towards making FPFs!